By Laura Landro

Diagnostic error is of increasing concern, studies show. A new report from QuantiaMD, a mobile and online physician community, found that almost half of 6,400 physicians surveyed said they encounter diagnostic errors — missed, late, or wrong diagnoses — at their practice at least monthly. About two-thirds said that up to 10% of misdiagnoses they have experienced have directly resulted in patient harm. Among the reasons: unusual patient presentation, failure to consider other diagnoses, inadequate patient history — and overtesting to avoid malpractice suits.

According to one study on quality in cancer diagnosis, the reported frequency of a diagnostic error made by oncologic pathologists ranges from 1% to 15%. And while the large majority of diagnostic errors do not result in severe harm, mild to moderate harm in the form of additional testing or diagnostic delays occurs in up to 50% of errors, the study found.

Hardeep Singh, chief of the health policy and quality program at Michael E. DeBakey VA Medical Center in Houston and the author of several studies on diagnostic errors, tells the Health Blog that second reviews of surgical pathology or cytology specimens find a “small but important group of errors,” and a growing number of health-care systems now require second readings in case types known to have substantial rates of variability between experts. Among the top areas of concern: cancers of the soft tissue, bladder and prostate; gynecologic malignancies; lung and colon cancers and brain tumors.

But Singh notes that the second opinions can also introduce new errors. And cost-benefit studies are needed to determine if the net benefit of second reads is worth the investment.

Radiologists at Johns Hopkins who provided second opinions on brain CT and MRI studies in one study found that 7.7% had significant discrepancies. When the final diagnosis was determined from pathology reports, clinical assessments and other imaging follow-up, the second opinion was correct in 84% of cases.

Jonathan Lewin, a co-author of the study and chief radiologist at Johns Hopkins, says that second opinions are especially critical when a diagnosis has been made by a doctor with less experience in the field. “Radiology is a challenging discipline, so there’s going to be a big difference between someone who sees 50 brain tumors a week versus someone who sees maybe ten a year,” Lewin says.

“Everyone doesn’t need to get a second opinion on their imaging studies,” he adds, but it is advisable for patients facing treatment for a new cancer diagnosis or those whose test results and symptoms don’t really add up to a clear diagnosis.

In a study of head and neck cancers sent for second opinions to pathologists at the University of California, San Francisco, researchers identified major disagreements in 16.3% of cases that would have resulted in significant differences in patient evaluation and management.

The National Cancer Institute’s cancer clinics offer free second-opinion services for patients with a variety of cancers. Crystal Mackall, chief of the pediatric oncology branch, says doctors may refer patients who have rare diseases, recurrent cancers or cancers that aren’t responding to treatment, who then may be enrolled in one of her clinical trials. But her unit also fields about 300 calls a year from parents or family members seeking to confirm a diagnosis or treatment plan.

Second opinions can be important when treatment decisions are difficult and patients are hearing different recommendations from different specialists. In breast cancer, for example, women may hear conflicting opinions from surgeons and radiation oncologists.

Michael Sabel, director of the University of Michigan Comprehensive Cancer Center Breast Cancer Clinical Outcomes Project and assistant professor of surgery, says a tumor board at the center resolves such conflicts, gathering different specialists to reach consensus about the best course of treatment for a particular patient.

In a study there, more than half of breast-cancer patients who sought a second opinion from the tumor board received a change in their recommended treatment plan. While sometimes the tumor board will catch something and earlier doctor didn’t see or a pathologist may disagree with the original diagnosis, there are other benefits to a second opinion. “Many women undergoing treatment don’t fully understand their options,” Sabel says. “Sometimes the benefit of a second opinion is to go through them again, and hear it from a different point of view to help their comprehension.”

Comments (1 of 1)

Medication dosing and interaction mistakes leading to harm, and surgical errors have been the focus of the patient safety movement, yet research shows that diagnostic errors outpace other causes of medical error by a factor of 3. Thankfully, diagnostic errors are now entering the patient safety "spotlight". For physicians, safety experts and patients with interest in diagnostic errors there is a new society, the Society for Improving Diagnosis in Medicine (SIDM). SIDM grew out of Diagnostic Errors in Medicine annual meeting which will be held for the fifth year at John Hopkins University from November 11-14. Information about the SIDM can be found at http://www.improvediagnosis.org/ . The society welcomes new members.
Art Papier MD
CMIO, Logical Imageshttp://www.visualdx.com diagnostic support
Associate Professor of Dermatology and Medical Informatics, Univ of Rochester School of Medicine